/*
 * Copyright 2017 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifndef SKSL_DFASTATE
#define SKSL_DFASTATE

#include "src/sksl/lex/LexUtil.h"

#include <vector>
#include <string>

struct DFAState {
    struct Label {
        std::vector<int> fStates;

        Label(std::vector<int> states) : fStates(std::move(states)) {}

        bool operator == (const Label &other) const
        {
            return fStates == other.fStates;
        }

        bool operator != (const Label &other) const
        {
            return !(*this == other);
        }

#ifdef SK_DEBUG
        std::string description() const
        {
            std::string result = "<";
            const char *separator = "";
            for (int s : fStates) {
                result += separator;
                result += std::to_string(s);
                separator = ", ";
            }
            result += ">";
            return result;
        }
#endif
    };

    DFAState() : fId(INVALID), fLabel({}) {}

    DFAState(int id, Label label) : fId(id), fLabel(std::move(label)) {}

    DFAState(const DFAState &other) = delete;

    int fId;

    Label fLabel;

    bool fIsScanned = false;
};

namespace std {
template <> struct hash<DFAState::Label> {
    size_t operator () (const DFAState::Label &s) const
    {
        size_t result = 0;
        for (int i : s.fStates) {
            result = result * 101 + i;
        }
        return result;
    }
};
} // namespace

#endif
